Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2007
Forfattere
Christer Magnusson Karl Thunes Hans Nyeggen Hans Overgaard Trond Rafoss Solveig Haukeland May Bente Brurberg K. A. Strandenæs Bjørn Økland Bonsak HammeraasSammendrag
The detection in 1999 of the pine wood nematode (PWN), Bursaphelenchus xylophilus, in Portugal triggered survey activities in many European countries. With the assumption that PWN would reach frequency 10 times lower than the native B. mucronatus and the requirement of a 95 % confidence limit suggested 2 995 samples to be required for a safe statement on the absence of PWN from the territory surveyed. Samples were taken from 10 circular areas with 50 km diameter erected from a point of import of risk materials. In the period 2000-2006 3 165 wood samples, 2 880 from Pinus sylvestris, 279 from Picea abies and 6 from unknown wood, were collected from 446 logging sites, in 84 municipalities and 13 counties. Of the total material 85 % of the samples came from cutting wastes, timber or lying trees. Wood showing signs of insect activity (incl. Monochamus) formed 73 % of the total material. Nematodes were recorded in 85 % of the samples. The order Rhabditida was most frequent, followed by the orders Aphelenchida, Tylenchida and Dorylaimida. Rhabditid nematodes were equally frequent in pine and spruce, while Aphelenchida (Aphelenchus, Aphelenchoides, Cryptaphelenchus, Seinura and Bursaphelenchus) and Tylenchida (Filenchus, Lelenchus, Ditylenchus, Deladenus and Nothotylenchus) tended to be more common in pinewood. Aphelenchoides was the most common genus. The genus Bursaphelenchus occurred in 1 % of the samples. B. mucronatus was detected in 0,3 % of the samples and most often in cutting waste of pine. The pine wood nematode (PWN), B. xylophilus, was not detected in this survey. The unexpected low natural occurrence of B. mucronatus indicates that the number of potential niches for PWN also is lower than expected, and hence it will be necessary to continue this surveillance program to reach 10 000 samples. The present zone sites in central and south-eastern Norway will be supplemented with 1-2 zone sites in southwestern region of the country. In the future these zone sites will function as permanent observation areas. Care will also be taken to collect all samples from detached wood with signs of Monochamus activity.
Forfattere
Thomas Hartnik Henning MatthiesenSammendrag
Piling as a foundation technique on cultural layers has the advantage that the amount of excavated material is reduced. On the other hand, piling can have an adverse impact on the preservation of cultural layers in the ground due to physical deterioration and by enhancing biological degradation. The study presented in this report aimed at assessing the effect of piling and associated construction techniques on the environmental conditions in cultural layers that control biological degradation. Physical and chemical investigations in two excavated soil profiles near Hotel Klubben in Tønsberg were performed where piling was used as a foundation technique, and where drillings had earlier indicated a reduced organic content and worse state of preservation of the deposits close to the pile. Environmental conditions were assessed conducting field and laboratory measurements of basic physical and chemical parameters, as well as measurements of redox sensitive parameters. The results of the measurements revealed high oxygen concentrations near the foundation wall of the building where the cultural layers had been exchanged by porous fill masses. While areas that were not affected by oxygen intrusion had iron and sulphate reducing conditions that represent good preservation conditions in cultural layers, redox conditions near the building were aerobic and nitratereducing. These conditions enhance degradation of cultural layers. Oxygen intrusion into the ground is most likely facilitated by coarse material that was refilled next to the building when a girder was built under the foundation walls of the building. This coarse material enables diffusion of air into cultural layers as well as percolation of oxygen rich rain water into the ground . A possible adverse effect of the pile on environmental conditions is totally overshadowed by the effect of the girder and refilling material and could not be detected. It was not possible to investigate the conditions closer than approximately 50 cm from the pile. Nor was it possible to investigate the conditions deeper than 2.2 m beneath the soil surface, and thus this report cannot conclude anything about the conditions and possible impacts outside the investigated area.
Forfattere
Heidi KnutsenSammendrag
Kulturlandskapet i fjordbygdene på Vestlandet er formet av det jordbruket som drives langs fjordene. Flyfoto viser tydelige endringer i landskapet, marginale arealer gror til med busker og trær, men også bakkeplanering, spesialisering og nye dyrkingsteknikker setter tydelige spor i landskapet.
Forfattere
Ievina Sturite Trond Maukon Henriksen Tor Arvid BrelandSammendrag
We have studied to what degree Italian ryegrass (Lolium multiflorum Lam.), white clover (Trifolium repens L.) and meadow fescue (Festuca pratensis L.) are able to preserve nitrogen (N) and phosphorous (P) in shoots and roots from one growing season to the next in a northern temperate climate. Field experiments were performed during four consecutive winters in central southeast Norway (60 degrees 42'N, 10 degrees 51'E), and N and P in plant biomass were measured in the autumn and in the spring. We also measured the contents of total N, total P and organic carbon (C) in seepage water that percolated through the aboveground plant material. Uptake of N and P in Italian ryegrass and white clover was substantially larger than in meadow fescue. The winter losses varied greatly from year to year, depending on the winter climate. On the average for all three of the plant species, the winter losses of N from aboveground biomass were 6, 35, 68 and 10% in the four experimental years, respectively. The corresponding P losses were 11, 36, 60 and 22%. On the average for all plant species and experimental years, 43 (+/- 12)% (S.E., n = 12) of the N, 34 (+/- 9)% of the P and 4 (+/- 1)% of the C that was lost from the aboveground plant biomass during the winter, was recovered in seepage water, basically as a nutrient pulse in melt water in early spring. The very low C recovery rate in seepage water suggested a considerable microbial growth on lost plant C. Assuming that all un-recovered plant C was consumed by microorganisms not included in measurements of the seepage water, modelling showed that microbial immobilisation theoretically might explain the unexpectedly low recovery rates of N and P. The study was not designed to investigate the possible effects of psychrophilic microbes on N and P cycling. Therefore, it is inconclusive and underlines the need for more knowledge on this matter. (c) 2006 Elsevier B.V. All rights reserved.
Forfattere
Elena A. Kasatkina Oleg I. Shumilov Paul E. Aspholm Natalia V. LukinaSammendrag
Among some of the mysteries of the Tunguska meteorite event, is the cause of the accelerated tree growth after 1908 in the catastrophe area (about 2000-2500 km^2). The main explanation of accelerated growth of old trees, was a result of decrease of competition level due to falling of considerable part of neighbour trees. We analyzed all available tree ring records (more than 100) including our own ones collected in the Taymir Region of Northern Siberia (72N; 105E) at a distance of about 1500 km to the North from the Tunguska catastrophe epicentre (61N; 102E). It was found that there were a considerable increase of tree ring growth in 1908 over a vast area of Siberia (60N-75N; 80E-110E) that at much more vast area (10^3 times more) than had been earlier considered. The similar effect was detected after the Chulym bolide explosion in 1984 (57.7N; 85.1E). Of course, the Chulym forest response area was some smaller taking into account incomparable powers of Tunguska and Chulym events). It is obvious that the interpretation mentioned above, of tree growth observed too far from epicentre, could hardly be accepted. A more likely hypothesis is that the growth of the trees became stimulated by the matter from comet that where spread over a large territory of Eurasia. It is generally believed that meteorites and comets delivered large amounts of simple organic composites to the early Earth. Another hypothesis is connected to NO produced during the event analyzed. For example, in time the Tunguska event the comet (probably fragment of the comet Enke) tail started to influence the Earth atmosphere several days before the fall of the meteorite causing optical anomalies observed mainly westwards from the place of TO explosion (Western Siberia, European Russia, Northern Europe). We discuss as well the role of "small signals" in simulation of biological object response. The work was supported by a grant from the Russian Foundation for Basic Research (grant N 05-04-97528), by the Program "Biodiversity and dynamics of gene pool" of the Russian Academy and by the Regional Scientific Program of the Murmansk region.
Forfattere
Mensur Vegara Thor S. Larsen Hans Magnus Gjøen Anders Kiessling Roger K. Abrahamsen Ole Hofstad Lars Helge Frivold Bal Ram Singh Roberto Garcia Geir-Harald Strand dag-ragnar blystad Åsmund AsdalSammendrag
The Norwegian Ministry of Foreign Affairs (MFA) has been funding an NORWEGIAN SOUTH EASTERN EUROPE (SEE) PROGRAMME IN AGRICULTURE; Competence transfer and institutional contact and co-operation between faculties of Agriculture, Forestry and Veterinary Medicine in South Eastern Europe, (2002 ?2005). The main objectives under this programme were: - To improve organising, content and quality of academic education and research in agriculture, veterinary medicine and forestry to meet with needs for qualified people in ongoing rebuilding after wars and to reach the general European level and standards. - Create functional and sustainable networks of regional institutions and professionals to support each other and cooperate for optimal use of limited available resources in the SEE region in a difficult rebuilding situation. The main activities were: - Research and development projects in the areas of animal sciences, crop and fodder production and use of GIS-methods in forestry and agriculture. - Support to development of staff and institutions in form of study stays, study material, covering of costs for laboratory analysis etc. related to M.Sc. and Ph.D. thesis work, guest lecturing and some equipment. - Support to reorientation of academic education in agriculture, forestry and veterinary medicine. - Support to regional networks, professional meetings, further development and use of the Programme web site and web-based teaching. The most important strategy in this Programme was to facilitate for institutional cooperation and network building between partners in the SEE area. Origin application (05/420-3, 07.12.06) to MFA, for budget of activities for the secon year 2007, was NOK 4.830.000. The MFA reduced applied budget approximately by 18%. Funding of NOK 4.000.000 was granted by the MFA for this program?s second year 2007. See UD bevilgningsbrev, 05/00396-12, from 19. April 2007, Appendix 1, page 48-51. According to the UD bevilgningsbrev budget and activities for the secon year 2007 wear redused, see NORAGRIC?s letter 05/420-3, 07.05.2007, e-mail 07.05.2007, page 45 and UD letter 05/00396-16, from 19 November 2007, page 46. See also e-mail Status report for UD Project nr. 2070061, 25.06.2007, page 47. The Norwegian University of Life Sciences (UMB), through Noragric, UMB?s Department for International Environment and Development Studies, has been responsible for the overall preparations, coordination and implementation of this programme. The programme?s Coordinator has also been part time active with scientific and education in several projects and activities. UMB/Noragric has been responsible for accounting and reporting for the programme. Programme activities include: ? Programme budgets for each projects and activities have been prepared. ? There have been preparations of agreements (54 agreements) between SEE/WB partners and Norwegian partners for the implementation of planned programme activities and transfer of funds for 2007. ? FINAL reports for the second year of the programme activities (2007) have been prepared ? for each of the 9 projects according to MFA?s template for project reporting.
Sammendrag
To obtain information that might help in the use of Neozygites floridana (Zygomycetes: Entomopthorales) in biological control of Tetranychus urticae (Acari: Tetranychidae), in strawberries and cucumbers we have tried to answer the following questions in a series of studies*): 1) When, and at what infection levels does N. floridana occur in T. urticae populations in field grown strawberries? 2) How does N. floridana survive harsh climatic conditions (i.e winter) in Norway? 3) Where do N. floridana infected T. urticae move and sporulate on a plant? 4) How do commonly used pesticides in strawberries affect N. floridana and T. urticae? 5) How can N. floridana be inoculated in augmentative microbial control of T. urticae? Results show that N. floridana infected and killed T. urticae in 12 out of 12 Norwegian strawberry fields studied. Infection levels up to 90% were observed, and the highest levels were observed late in the season. The infection levels throughout a season varied considerably. N. floridana was observed to over-winter as hyphal bodies in hibernating T. urticae females throughout the winter. Cadavers with resting spores were found from October to the end of January. Cadavers then probably disintegrated, and resting spores were left on leaves, soil, etc. In a bioassay where a Norwegian N. floridana isolate was tested for numbers and distance of spores thrown at three different temperatures (13o, 18o, 23o C), results show that the highest numbers of spores (1886 and 1733 per cadaver) were thrown at 13o and 18o compared to 23o C (1302 per cadaver). Spores were thrown at the same distance (up to about 6 mm) at all three temperatures when cadavers were placed with dorsal side facing up. Cadavers placed with dorsal side down (hanging) threw equal numbers of spores up (on the underside of the leaf in nature) and down (on the leaf below). The effects of pesticides used in strawberries on the N. floridana infection level were studied to evaluate factors that might be important for conservation biological control. The pesticides tested were three fungicides; Euparen (tolylfluanid), Teldor (fenhexamid), Switch (cyprodinil +fludioxonil) and one acaricide/ insecticide: Mesurol (methiocarb). The experiment indicated that all three fungicides affect N. floridana negatively but that Euparen might be the least harmful. Mesurol did not affect N. floridana. Our attempt to inoculate N. floridana artificially in a strawberry field has not yet been successful, but we now work on promising methods for inoculation of N. floridana in T. urticae populations in greenhouse cucumbers. More detailed results from the studies referred to in this abstract will soon be published elsewhere.
Sammendrag
High mortality among chicks, due to fragmentation and changes in habitat caused by commercial forestry, is considered one of the main reasons for the general decline in capercaillie Tetrao urogallus in boreal forests. Using GPS satellite telemetry, we studied the movement patterns of young capercaillie broods: 1) to test if this new technology could be applied to gain more detailed insight into behaviour and habitat selection at a small spatial scale, and if so, 2) to compare the broods' relative use of planted and older, naturally regenerated forests. Hens of four broods with chicks 2-7 days old were captured and fitted with 90-g backpacks containing GPS units and VHF transmitters. The GPS units were programmed to record positions every 15 minutes, the shortest interval possible. With a storage capacity of 450 positions, movements could be monitored for ca 4.5 days. In our study area (Varaldskogen) with moderate topography, the GPS technology performed quite well. A total of 1,277 positions were obtained (84% of potential maximum), of which 77% were within 20 in of the true position of the brood. The movement patterns of the four broods were quite similar, with a mean speed of 83.2 m +/- 9.9 (SE) per hour during the 4.5-day tracking period. Broods moved almost continuously during the 24-hour cycle, presumably foraging, although their speed was slower at night. The two oldest broods whose initial age was seven days moved faster than the two younger broods whose initial age was two and three days, respectively. Strong autocorrelation among successive positions made us examine habitat selection using a binominal choice method for each brood separately. When broods were inside old 'natural' forest, they remained there instead of moving into plantations. When inside plantations, they did not discriminate between remaining there and moving into nearby old forest, but they tended to move faster in plantations than in old forest. Clearly, the new, cost-effective GPS telemetry offers new and better opportunities for studying small-scale brood movement. Very frequent and accurate positions can be obtained without either disturbing the birds or leaving scent marks that may attract predators.
Sammendrag
Kvitkløver egnar seg godt i slåtteng også under norske tilhøve. Avlingsnivået var på høgde med raudkløvereng. Samla over to forsøksår gav kvitkløvergrassurfôr eit høgare dagleg opptak av tørrstoff og råprotein enn raudkløvergrassurfôr, men effekten av kløverart på dei fleste produksjonsparametrane var liten. Raudkløvergrassurfôr gav mjølk med gunstigare feittsyresamansetjing og mjølk med mye høgare innhald av isoflavon ("kløverplanteøstrogen"), uansett kraftfôrnivå, enn kvitkløvergrassurfôr. Særleg var innhaldet av equol høgt. Av planteøstrogena, er det equol ein trur verkar preventivt t.d. mot bryst- og prostatakreft.
Sammendrag
Neozygites floridana is a fungus in the order Entomophthorales that infects and kills the two-spotted spider mite, Tetranychus urticae. The fungus is therefore of interest for the biological control of T. urticae. To obtain information that might help in the use of this fungus under practical conditions in strawberries and cucumbers we have tried to answer the following questions in a series of studies*): 1) When, and at what infection levels does N. floridana occurre in T. urticae populations in fieldgrown strawberries? 2) How and where does N. floridana survive harsh climatic conditions (i.e winter) in Norway? 3) How and where does N. floridana infected T. urticae move and sporulate on a plant? 4) How do commonly used pesticides in strawberries affect N. floridana and T. urticae? 5) How can N. floridana be inoculated in augmentative microbial control of T. urticae? Results show that N. floridana infected and killed T. urticae in 12 out of 12 Norwegian strawberry fields studied. Infection levels up to 90% were observed, and the highest levels were observed late in the season. The infection levels throughout a season varied considerably. N. floridana was observed to overwinter as both hyphal bodies in hibernating T. urticae females from October to at least February at temperatures as low as -20o C. Cadavers with resting spores were found from October to the end of January. Cadavers then probably disintegrated, and resting spores were left on leaves, soil, etc. In a bioassay where a Norwegian N. floridana isolate was tested for numbers and distance of spores thrown at three different temperatures (13o, 18o, 23o C), preliminary results show that high numbers of spores (ca 1300-1900 per cadaver) were thrown at all three temperatures. Further, spores were thrown about the same distance (up to about 6 mm) at all three temperatures. The effects of pesticides used in strawberries on the N. floridana infection level were studied to evaluate factors that might be important for conservation biological control. The pesticides tested were three fungicides; Euparen (tolylfluanid), Teldor (fenhexamid), Switch (cyprodinil +fludioxonil) and one acaricide/ insecticide: Mesurol (methiocarb). The experiment indicated that all three fungicides affect N. floridana negatively but that Euparen might be the least harmful. Mesurol did not affect N. floridana. Our attempts to inoculate N. floridana artificially in a strawberry field has not yet been successful, but we now work on promising methods for inoculation of N. floridana in T. urticae populations in greenhouse cucumbers. More detailed results from the studies referred to in this abstract will soon be published elsewhere.